从JavaScript按名称调用PHP函数

Question

I have a javascript function that's executed on a button click and I have an included file containing all my PHP functions. One of the PHP functions returns me an array of filenames encoded as a JSON object. I'd like to call this function from my Javascript function so that I can use the array. I know I can call a PHP file which would run but in this case I only want to call one specific named method.

I tried the following but couldn't get it to work (Console error: Unexpected < )

function getPHPArray(){
    var picArray;
    picArray = <?php getPicArrayJson(); ?>;
}

Can this be done using XMLHttpRequest or do I need to find another method? (If reasonably possible I'd prefer straight Javascript over JQuery but I can use JQuery if it makes this significantly easier)

If so how?

My PHP method is as follows:

function getPicArrayJson(){
    global $fileArrayString;
    If (!empty($fileArrayString)){
        echo json_encode($fileArrayString);
    }
}

My JavaScript so far:

function getPHPArray(){
    var xmlhttp;
if (window.XMLHttpRequest){
    xmlhttp=new XMLHttpRequest();
}
else {// code for IE6, IE5
    xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}   
xmlhttp.open("POST", "phpFunctions.php?name=getPicArrayJson", true);   
xmlhttp.send();
}

Answer 1

This is essentially a Remote Procedure Call . For use with PHP, I'd check out JSON-RPC PHP .

---

Anyway, here's a basic way you can do it without much complexity to your app. You will have to make an ajax request to the server. The idea for you here is to use call_user_func .

call_user_func("getPicArrayJson");

You can use

call_user_func($_POST["name"]);

But I highly recommend that you only allow certain functions to be called

---

phpFunctions.php

$allowed_functions = array("getPicArrayJson");
$name              = $_POST["name"];

function getPicArrayJson() {
  $pics = array("1.jpg", "2.jpg");
  return json_encode($pics);
}

// legal function
if (in_array($name, $allowed_functions)) {
  header("Content-Type: application/json");
  $json = call_user_func($name);
  die($json);
}

// invalid access
else {
  // Error 400
}

Then do you Ajax request per normal

...
xmlhttp.open("POST", "phpFunctions.php?name=getPicArrayJson", true);   
xmlhttp.send();

---

ps my own two cents, I would use a GET request for this. Following RESTful API conventions for web services , a POST request would only be used to create a new element.